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At 1524h, On the afternoon of January 15th 2009, US Airways Flight 1549 was cleared for takeoff from Runway 4 at New York's La Guardia airport. The airplane carried 150 passengers and 5 flight crew, on a flight to Charlotte Douglas, North Carolina. The Airbus A320's twin CFM56 engines had been serviced just over a month prior to the flight. The plane climbed to a height of 859m (2818 feet) before disaster struck.

Passengers reported hearing several loud bangs and then flames being visible from the engines' exhaust. Shortly thereafter the 2 engines shut-down, robbing the Airbus of thrust and its primary source of electrical power.

At this point the Captain took over from the First officer and between them they spent the next 3 minutes both looking for somewhere to land, while also desperately trying to restart their aircraft's engines.

What Happened?
A flock of birds had crossed the path of the Airbus and several had struck the plane. Both engines had ingested birds an…

An amused but slightly exasperated developer once turned to me and said "I not only have to get all the features correct, I have to get the errors correct too!". He was referring to the need to implement graceful and useful failure behaviour for his application.

Rather than present the customer or user with an error message or stack trace - give them a route to succeed in their goal. E.g. Find the product they seek or even buy it.

Graceful failure can take several forms, take a look at this Bing [search] Suggestions bug in Internet Explorer 11.

As you can see, the user is presented with a useful feature, most of the time. But should they paste a long URL into the location bar - They get hit with an error message.

There are multiple issues here. What else is allowing this to happen to the user? The user is presented with an error message - Why? What could the user possibly do with it? Bing Suggestions does not fail gracefully.I not only have to get all the features correct, I…

Many of my clients ask me to test their content management and processing systems. Often this involves investigating how the software handles images of various sizes as well as text of various lengths or types.

Earlier this year Boeing 787 engineers were given some new instructions by the FAA (The US government's: Federal Aviation Authority). They were informed that if the aeroplane's electrical generators were left running for 248 days, they would enter fail-safe mode.
In plain English: they will stop producing electrical power. This short video looks into why that might be and how this information can hep us test our software.

In many of my clients, more effort is spent on 'test automation' than on other forms of testing or quality assurance. That can be the right choice, for example, I worked on a Data Warehousing project where we needed to write some test automation before we could test the data and its processing.

Many other projects in different technology areas also spend a lot of time on their test automation. To be precise, they spend an increasing amount of time fixing & maintaining old 'tests' and 'frameworks'.

There are great tools around to help us write these automated checks quickly. But as with many software systems: maintenance, in the long term, is where the time and money goes. That is why I'm surprised we don't use short term automation more. We have the skills.

One good example of short term automation is Bug Automation. A simple script / executable that recreates or demonstrates a bug. This isn't a new idea, I've been doing it for years and I …